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31.
Industrial clusters have attracted increasing attention as important locations of innovation. Therefore, several countries have started promotion policies for industrial clusters. However, there are few empirical studies on cluster policies. This paper examines the effects of the “Industrial Cluster Project” (ICP) in Japan on the R&D productivity of participants, using a unique dataset of 229 small firms, and discusses the conditions necessary for the effective organization of cluster policies. Different from former policy approaches, the ICP aims at building collaborative networks between universities and industries and supports the autonomous development of existing regional industries without direct intervention in the clustering process. Thus far, the ICP is similar to indirect support systems adopted by successful European clusters. Our estimation results suggest that participation in the cluster project alone does not affect R&D productivity. Moreover, research collaboration with a partner in the same cluster region decreases R&D productivity both in terms of the quantity and quality of patents. Therefore, in order to improve the R&D efficiency of local firms, it is also important to construct wide-range collaborative networks within and beyond the clusters, although most clusters focus on the network at a narrowly defined local level. However, cluster participants apply for more patents than others without reducing patent quality when they collaborate with national universities in the same cluster region.  相似文献   
32.
Analogs of methcathinone (MC), a psychoactive stimulant, are in circulation all over the world. These analogs have been assumed to be unstable in alkaline solutions, as is MC itself. The aims of this study were: (i) to identify the degradation products of 4-methylmethcathinone (4-MMC), a typical MC analog, in solution at pH 12 and to determine the degradation pathway, (ii) to investigate the effects of antioxidants such as l-ascorbic acid and sodium sulfite on the degradation of 4-MMC, and (iii) to investigate the stability of seven MC analogs (4-MMC, 4-, 3-, or 2-fluoromethcathinone, 4-methoxymethcathinone, N-ethylcathinone, and N,N-dimethylcathinone) in solutions at different pHs.1-(4-Methylphenyl)-1,2-propanedione (MPPD), 4-methylbenzoic acid (MBA), N,4-dimethylbenzamide (DMBA), and N-acetyl-4-MMC (N-Ac-4-MMC) were identified as the degradation products of 4-MMC in pH 12 solution by gas chromatography-mass spectrometry. There are two degradation pathways for 4-MMC as follows: (a) 4-MMC→MPPD→MBA→DMBA and (b) 4-MMC→N-Ac-4-MMC. Oxidants such as dissolved oxygen were presumed to be involved in this degradation based on the suppressive effects generated by the addition of antioxidants. All of the seven MC analogs tested were stable in acidic (pH 4) solution but degraded in neutral-to-basic solutions. Their degradation rates increased with increasing pH, and varied with their chemical structures. These findings will be very useful for not only forensic analysis but also future pharmacokinetic analysis.  相似文献   
33.
Conventional PCR-based genotyping is useful for forensic testing but cannot be used to determine parental origins of alleles in DNA specimens. Here we describe a novel method of combined conventional genotyping and PIA typing (parentally imprinted allele typing) at a minisatellite region upstream from the H19 locus. The PIA typing uses two sets of primers and DNA digested with methylation-sensitive Hha I enzyme. The first amplification produces only the methylated fragment of paternal H19 allele, and the second detects polymorphism in the minisatellite. Hence, this distinguishes paternal and maternal alleles by difference in the DNA methylation. Furthermore, the polymorphism in this polymorphic locus was examined using 199 unrelated Japanese and 171 unrelated Germans, their polymorphism information content being 0.671 and 0.705, respectively. Feasibility of this typing is demonstrated for six families, and the usefulness is shown by application to paternity testing.  相似文献   
34.
We present here a fatal poisoning case involving verapamil, metoprolol and digoxin. A 39-year-old male was found dead in his room, and a lot of empty packets of prescribed drugs were found near the corpse. The blood concentrations of verapamil, metoprolol and digoxin were 9.2 microg/ml, 3.6 microg/ml and 3.2 ng/ml, respectively. The cause of death was given as cardiac failure, hypotension and bradycardia due to a mixed drug overdose of verapamil, metoprolol and digoxin, based on the results of the autopsy and toxicological examination. We speculate that the toxicity of verapamil is potentiated by drug interaction with metoprolol and digoxin.  相似文献   
35.
At the end of 1952 the UK proposed to revitalise the ANZAM arrangement by concentrating it more closely on the defence of British interests in Malaya. Hitherto ANZAM had focused almost completely upon planning for the wartime defence of sea communications in the Southwest Pacific. This article explains why the UK sought to revitalise ANZAM, and why Australia accepted the British proposal. The British proposal arose from the adoption by the UK of a strategy of nuclear deterrence which led it to project both a future reduction of British conventional forces available for overseas commitments, and a greater reliance upon Commonwealth partners for the protection of British interests in Malaya. It also represented an attempt to reduce the value of the ANZUS security treaty, signed in early September 1951. Australia accepted the British proposal that Commonwealth partners should shoulder a heavier burden in Malaya as a way of preserving the value of ANZUS and of adjusting to the future reduction of the British military presence in Asia.  相似文献   
36.
Direct identification of copper phthalocyanine (CuPc) and chlorinated CuPcs in paints for discrimination between blue automobile paints by means of laser desorption mass spectrometry (LDMS) in the absence of a matrix is reported. The models consisted of eight commercially available CuPc pigments applied to a piece of plain white coating paper. The relationship between the peak intensity at m/z 575 of the CuPc, the number of pulsed laser shots, and laser power was compared to optimize laser abrasion. LDMS analysis of the model paints demonstrated that all characteristic components of the CuPc pigments in the paint films were in good agreement with those in the powder pigments. Further, the chlorinated CuPcs in the paint films could be distinguished. A quantity of 42 blue paint films, representing the paints used for painting Japanese domestic trucks, was examined by LDMS analysis. Results indicate that the paints can be classified into four categories based on the chlorinated CuPc components of the paints. Therefore, LDMS spectra of CuPc pigments would be useful for the identification of paints in forensic investigations. Herein, we report the successful identification of the CuPcs in a paint smear on the frame of a bicycle damaged in a hit-and-run accident, using the LDMS spectra.  相似文献   
37.
To evaluate the usefulness of forensic autopsies in determining latent prostate cancer (PC) prevalence, we examined latent PC prevalence from autopsies and compared our findings between decedents with and without cancer. Data from forensic autopsies performed in Japan from 2004 to 2014 were obtained. For each prostate, histopathological examinations were performed in both the base and the apex sections. Three hundred and seventeen Japanese decedents were selected for analysis. The mean age of decedents was 56.4 ± 17.8 years (range, 14–94 years). Among this population, 39.4% died suddenly of disease and 60.6% died of external causes. Latent PC was identified in 45 (14.2%) decedents, who ranged from 27 to 93 years old (mean, 71.1 ± 12.9 years). The prevalence of clinically significant PC with a Gleason score of 7 or more was 8.8%, and the rate increased with age. Fifteen males had cancers other than PC. The prevalence of overall latent PC was significantly higher for those with cancer compared with those without (40.0% vs. 12.9%; P = 0.003). In this study, the use of forensic autopsy materials provided the opportunity to obtain a more accurate natural history of PC, as the decedents in this situation would have been more likely to have died suddenly while behaving as normal prior to death, and less likely to have been impacted by long-term medical interventions.  相似文献   
38.
Impurities in 48 methamphetamine (MA) samples were analyzed by liquid-liquid extraction (LLE) and headspace solid-phase microextraction (HS-SPME) methods. MPS-2 autosampler was used to improve reproducibility of SPME method, and nonadecane (C(19)) diluted with potassium bromide (KBr) powder was used as an internal standard for standardizing retention time. Impurities identified by SPME method showed different patterns compared with LLE method. Non-volatile impurities like methamphetamine dimer were not identified by SPME method, but some volatile impurities like diphenylketone, caprolactam and lots of unknowns were identified only by SPME method. 1-Phenyl-2-propanone (P2P), 1-phenyl-2-propanol and benzylcyanide peaks could be discriminated clearly by SPME method without interference of amphetamine, an artifact originates from MA degradation. Differences in the impurity patterns resulted in different clustering results. When 48 MA samples were classified into 5 LLE and 5 SPME clusters, cross-matching of the clusters resulted in 8 sub-clusters. It shows that combination of the different extraction methods can distinguish the differences which cannot be distinguished by LLE or SPME method alone, and can improve reliability of the profiling results.  相似文献   
39.
The problem of substance abuse in Japan is centered around methamphetamine. The current article discusses the prevalence of methamphetamine use, legal controls against it, and a recently conducted study on recidivism in Japan. It also describes features of a newly initiated drug treatment program in Japanese prisons, its origin and differences from the original program. The article concludes with discussing the challenges faced by the newly initiated program.  相似文献   
40.
Haplotypes and allele frequencies of 17 Y-chromosomal short tandem repeat (Y-STR) markers were examined using the AmpFlSTR Yfiler PCR Amplification Kit (Applied Biosystems) in a population sample of 1166 Japanese male volunteers in 6 prefectures: Miyagi, Yamagata, Osaka, Tottori, Fukuoka, and Okinawa. A total of 1058 haplotypes were observed from 1166 males, and the most common haplotype detected in 12 males had a frequency of 1.03% and the discrimination capacity was 0.907. The RST analysis showed statistically significant differences between Okinawa and the other subpopulations.  相似文献   
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